1. Field of Invention
The present invention relates to facilitating the use of two or more wireless communication mediums in a device, and more specifically, to optimizing operation of at least one wireless medium in the device using information from another wireless medium.
2. Background
As communication technology evolves, the use of wireless communication has moved from a luxury to an integral part of today's society. A wireless communication device (WCD) may communicate using a multitude of mediums. These communication networks may be employed in various applications depending on the requirements of a given situation. Characteristics determining an appropriate network include the type of information to be transmitted, the expected transmission distance, the required speed of communication, the sensitivity of the information (security), the cost of use, the number of sources/recipients, etc.
Cellular networks support communication over large geographic areas. These network technologies have commonly been divided by generations, starting in the late 1970s to early 1980s with first generation (1G) analog cellular telephones that provided baseline voice communication, to modern digital cellular telephones. GSM is an example of a widely employed 2G digital cellular network communicating in the 900 MHZ/1.8 GHZ bands in Europe and at 850 MHz and 1.9 GHZ in the United States. This network provides voice communication and also supports the transmission of textual data via the Short Messaging Service (SMS). SMS allows a WCD to transmit and receive text messages of up to 160 characters, while providing data transfer to packet networks, ISDN and POTS users at 9.6 Kbps. The Multimedia Messaging Service (MMS), an enhanced messaging system allowing for the transmission of sound, graphics and video files in addition to simple text, has also become available in certain devices. Soon emerging technologies such as Digital Video Broadcasting for Handheld Devices (DVB-H) will make streaming digital video, and other similar content, available directly to a WCD. While long-range communication networks like GSM are a well-accepted means for transmitting and receiving data, due to cost, traffic and legislative concerns, these networks may not be appropriate for all data applications.
Short-range wireless networks provide communication solutions that avoid some of the problems of large cellular networks. Bluetooth™ is an example of a short-range wireless technology quickly gaining acceptance in the marketplace. A 1 Mbps Bluetooth™ radio may transmit and receive data at a rate of 720 Kbps within a range of 10 meters, and may transmit up to 100 meters with additional power boosting. Enhanced data rate (EDR) technology also available may enable maximum asymmetric data rates of 1448 Kbps for a 2 Mbps connection and 2178 Kbps for a 3 Mbps connection. A user does not actively instigate a Bluetooth™ network. Instead, a plurality of devices within operating range of each other may automatically form a network group called a “piconet”. Any device may promote itself to the master of the piconet, allowing it to control data exchanges with up to seven “active” slaves and 255 “parked” slaves. Active slaves exchange data based on the clock timing of the master. Parked slaves monitor a beacon signal in order to stay synchronized with the master. These devices continually switch between various active communication and power saving modes in order to transmit data to other piconet members. In addition to Bluetooth™ other popular short-range wireless networks include WLAN (of which “Wi-Fi” local access points communicating in accordance with the IEEE 802.11 standard, is an example), Wibree™, WUSB, UWB, ZigBee (802.15.4, 802.15.4a), and UHF RFID. All of these wireless mediums have features and advantages that make them appropriate for various applications.
More recently, manufacturers have also begun to incorporate various resources for providing enhanced functionality in WCDs (e.g., components and software for performing close-proximity wireless information exchanges). Sensors and/or scanners may be used to read visual or electronic information into a device. A transaction may involve a user holding their WCD in proximity to a target, aiming their WCD at an object (e.g., to take a picture) or sweeping the device over a printed tag or document. Near field communication technologies include machine-readable mediums such as radio frequency identification (RFID), Infra-red (IR) communication, optical character recognition (OCR) and various other types of visual, electronic and magnetic scanning are used to quickly input desired information into the WCD without the need for manual entry by a user.
While short-range communication networks like Bluetooth™ and WLAN can be convenient, they may also be somewhat limited in their application due to the unregulated nature of their operation. For example, interference created by a plurality of closely-situated apparatuses that emit signals operating in the same frequency range is a known problem in the art. More specifically, because wireless mediums like Bluetooth™ and WLAN operate in an unlicensed frequency band, other systems emitting radio waves in this band (e.g., other short-range radio and wireless networks, electronic emissions from microwave ovens, power systems, etc.) may cause background noise. This may limit the amount of channels on which a wireless communication medium may operate. In addition, interference from the proximal operation of other signal sources during communication on one or more radio channels may result in packets being lost, which may require the retransmission of this lost information and an overall reduction to wireless communication medium performance.
This impact in performance may occur with respect to speed, quality, energy conservation, etc. For example, wireless communication mediums that lack the ability to quickly identify communication channels on which potential target devices are operating (e.g., access points or other wireless devices) and/or the ability to exclude problematic communication channels must scan all potential communication channels, regardless of the current channel condition. The time and energy required to scan each of the channels in the allowed bandwidth may then become a fixed time and power burden that may be deemed, in some instances, to be a waste of resources when no available channels exist, or no other devices are within effective communication range of the wireless communication medium.